Ravi Bangoria [Tue, 16 Feb 2016 16:21:35 +0000 (21:51 +0530)]
libdwfl: Check for kernel debuginfo file without .debug extension as well
Elfutils, looking for kernel debuginfo file, tries to find it at
various places. If elfutils finds /boot/vmlinu*x* file, it checks
for debufginfo section. If debuginfo is not present, it saves it as
'main elf' and continue looking for debuginfo file having .debug
extension i.e. vmlinux-RELEASE.debug.
'Ubuntu on powerpc' installs kernel as /boot/vmlinux and installs
debuginfo without any extension as /usr/lib/debug/boot/vmlinux-RELEASE
and hence, elfutils is not able to find the debuginfo file.
Here is the launchpad bug for the same:
https://bugs.launchpad.net/ubuntu/+source/systemtap/+bug/1537125
This patch adds functionality to search for a kernel or debuginfo file
both with and without .debug extension.
Signed-off-by: Ravi Bangoria <ravi.bangoria@linux.vnet.ibm.com> Signed-off-by: Mark Wielaard <mjw@redhat.com>
Mark Wielaard [Sat, 13 Feb 2016 19:00:37 +0000 (20:00 +0100)]
readelf: Warn when uncompressing fails and error when gelf_getshdr fails.
After decompressing we want to get the new shdr. This can theoretically
fail so we have to check. Also warn the user if a section couldn't be
uncompressed.
Mark Wielaard [Sat, 13 Feb 2016 18:36:50 +0000 (19:36 +0100)]
libdw: Fix bad free on invalid data in dwarf_getsrclines.c.
If the last dir name wasn't zero terminated we goto invalid_data
and might free the wrong data because we believe ndirlist is valid.
Don't update ndirlist until we are sure we will use all dirs.
Mark Wielaard [Thu, 11 Feb 2016 12:20:59 +0000 (13:20 +0100)]
libdwfl: Check result of gelf_get* calls in relocate.c
For corrupted ELF files gelf_get calls might fail in which case it
is better to immediately return an error instead of using the NULL
result and crashing.
Mark Wielaard [Thu, 11 Feb 2016 11:46:03 +0000 (12:46 +0100)]
libdwfl: Check result of gelf_update_* calls in relocate_section.
For corrupted ELF files the gelf_update calls might fail in which case it
is better to immediately return an error message instead of (silently)
continuing.
Mark Wielaard [Fri, 12 Feb 2016 14:04:00 +0000 (15:04 +0100)]
libebl: Don't assume ELF notes are "GNU" when unknown, recognize "Go" notes.
We used to assume any unknown ELF note provider name was "GNU" and didn't
recognize any of the "Go" provider types. We now check the provider name
explictly in ebl_object_note_type_name and recognize the following Go
note names: PKGLIST, ABIHASH, DEPS and BUILDID. But there is no attempt
yet in ebl_object_note to decode the description of these notes.
Mark Wielaard [Tue, 9 Feb 2016 15:10:22 +0000 (16:10 +0100)]
config: Check for and use gcc -Wlogical-op and -Wduplicated-cond.
Both -Wlogical-op and -Wduplicated-cond may produce useful warnings.
But we have to check them first. Older versions of gcc had a -Wlogical-op
that warned on some constructs using macros that are not erronious.
Only GCC6 has -Wduplicated-cond.
Mark Wielaard [Tue, 9 Feb 2016 13:18:49 +0000 (14:18 +0100)]
elflint: Fix sh_entsize check when comparing SHT_HASH and SHT_GNU_HASH.
GCC6 -Wduplicated-cond found the following issue:
elflint.c: In function ‘compare_hash_gnu_hash’:
elflint.c:2483:34: error: duplicated ‘if’ condition [-Werror=duplicated-cond]
else if (hash_shdr->sh_entsize == sizeof (Elf64_Word))
~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
elflint.c:2448:29: note: previously used here
if (hash_shdr->sh_entsize == sizeof (Elf32_Word))
~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
Which is correct, a Word in both Elf32 and Elf64 files is 4 bytes.
We meant to check for sizeof (Elf64_Xword) which is 8 bytes.
Also fix the section index and name in the error message.
The reason we probably didn't see this issue before is that SHT_HASH
sections really always should have sh_entsize of 4 even on 64bit arches.
There are however a couple of arches with mistakes in their sysv ABI.
See libelf/common.h. This also would only be triggered if on such an
architectures when the ELF file would have both a SHT_HASH and SHT_GNU_HASH
section and elflint would try to compare those sections.
Add an example testfile-s390x-hash-both to run-elflint-test.sh.
Mark Wielaard [Thu, 4 Feb 2016 08:53:41 +0000 (09:53 +0100)]
libelf: elf_getdata should not adjust alignment for SHT_NOBITS sections.
In commit c0748e "libelf: More checking of valid sh_addralign values." we
adjusted bogus alignment of data buffers if they were greater than the
offset of the data in the file. This works OK, except when there is no
data in the file. So make sure to not adjust any NOBITS sections.
Also adds a test that shows the issue and makes sure elflint is called
with --gnu in run-strip-test.sh.
Mark Wielaard [Wed, 13 Jan 2016 16:16:48 +0000 (17:16 +0100)]
libelf: Add ELF compression types and defines to libelf.h for older glibc.
Older glibc elf.h might not define the new ELF compression defines and
types. If not just define them in libelf.h directly to make the libelf
headers work on older glibc systems.
Also include a testcase to check the libelf headers build against the
system elf.h.
Mark Wielaard [Sat, 9 Jan 2016 21:09:48 +0000 (22:09 +0100)]
libebl: Fix missing brackets around if statement body.
GCC6 [will have] a nice new warning that showed a real bug:
elfutils/libebl/eblobjnote.c: In function ‘ebl_object_note’:
elfutils/libebl/eblobjnote.c:135:5: error: statement is indented as if it were guarded by... [-Werror=misleading-indentation]
switch (type)
^~~~~~
elfutils/libebl/eblobjnote.c:45:3: note: ...this ‘if’ clause, but it is not
if (! ebl->object_note (name, type, descsz, desc))
^~
And indeed, it should have been under the if, but wasn't because of missing
brackets. Added brackets (and reindent).
Mark Wielaard [Tue, 1 Dec 2015 13:55:07 +0000 (14:55 +0100)]
elfcompress: New utility.
Usage: elfcompress [OPTION...] FILE...
Compress or decompress sections in an ELF file.
-f, --force Force compression of section even if it would
become larger
-n, --name=SECTION SECTION name to (de)compress, SECTION is an
extended wildcard pattern (defaults to
'.?(z)debug*')
-o, --output=FILE Place (de)compressed output into FILE
-p, --permissive Relax a few rules to handle slightly broken ELF
files
-q, --quiet Be silent when a section cannot be compressed
-t, --type=TYPE What type of compression to apply. TYPE can be
'none' (decompress), 'zlib' (ELF ZLIB compression,
the default, 'zlib-gabi' is an alias) or
'zlib-gnu' (.zdebug GNU style compression, 'gnu'
is an alias)
-v, --verbose Print a message for each section being
(de)compressed
-?, --help Give this help list
--usage Give a short usage message
-V, --version Print program version
Mark Wielaard [Fri, 18 Dec 2015 14:51:37 +0000 (15:51 +0100)]
elflint: Recognize and check SHF_COMPRESSED section flag.
SHF_COMPRESSED is a valid section flag, it can optionally be on any special
section, but it cannot be used on NOBITS sections or together with SHF_ALLOC.
A section that has SHF_COMPRESSED set must have a valid Chdr.
Mark Wielaard [Wed, 30 Dec 2015 00:39:29 +0000 (01:39 +0100)]
libelf: Make elf_strptr index correctly into compressed section data.
elf_strptr indexes into the section data. This is defined as index into
the uncompressed data of the section. If the section is compressed make
sure the uncompressed data is available, but don't really decompress the
section header (elf_getdata will still return compressed data).
Mark Wielaard [Tue, 20 Oct 2015 23:30:44 +0000 (01:30 +0200)]
readelf: Handle compressed sections and extend -z to cover -x and -p.
When printing a (non-string, non-data) section use uncompressed data when
possible. For dumping hex and string sections (-x and -p) -z will dump the
uncompressed data (otherwise the compressed data is dumped).
-z, --decompress Show compression information for compressed
sections (when used with -S); decompress section
before dumping data (when used with -p or -x)
Includes test cases for ET_REL files using compressed relocation (target)
debug sections to test libdwfl transparent uncompression of sections.
Mark Wielaard [Wed, 30 Dec 2015 13:39:18 +0000 (14:39 +0100)]
libdwfl: Use elf_compress[_gnu] to decompress string, symbol and reloc data.
This makes usage of the libdwfl symbol functions work out of the box even
when some sections (string, symbol or xndx) are compressed. For ET_REL
files this makes relocations just work by making sure the target section
is decompressed first before relocations are applied.
Mark Wielaard [Wed, 30 Dec 2015 13:18:40 +0000 (14:18 +0100)]
libdw: Use elf_compress[_gnu] to uncompress debug section data.
libdw used its own code for decompressing GNU style .zdebug sections.
Using elf_compress and elf_compress_gnu instead makes it possible to
transparently use either GNU style or ELF style compressed data.
Mark Wielaard [Thu, 19 Nov 2015 23:12:37 +0000 (00:12 +0100)]
libelf: Add elf32_getchdr, elf64_getchdr and gelf_getchdr.
Elf_Data of a compressed section has type ELF_T_CHDR. This type can be
xlated to the file or memory representation. This will make sure the Chdr
is in the correct endianess. The compressed data following the Chdr isn't
translated.
Mark Wielaard [Thu, 31 Dec 2015 22:16:28 +0000 (23:16 +0100)]
elflint: Add _edata and _end to the list of possibly dangling gnuld symbols.
gnuld might keep dangling/unused symbols around (see sourceware PR13621).
Add _edata (end of initialized data address) and _end (end of uninitialized
data address) to that list. They might have been added by gnuld even if
there is no such [un]initialized data. Also add the double underscore
variants which are used on some architectures.
Mark Wielaard [Thu, 31 Dec 2015 22:03:20 +0000 (23:03 +0100)]
tests: elfstrmerge warn about STT_SECTION symbol for shstrhndx.
Old linkers might have created an STT_SECTION symbol for the section
header string table section, which isn't actually used. For now just
warn about such symbols. If such a symbol would actually really be used
(but why?) then we would have to handle it by removing it and rewriting
the symbol table.
This is a testsuite only change, but includes an extra test with files
that have such STT_SECTION symbols to make sure it will be handled in
case we "upgrade" the elfstrmerge test to a real utility.
libdwfl: make the unwinder aware of the backend defined ra_offset.
Ebl backends can define an offset that must be applied to the value of
the "return address register" defined in the CFI ABI information.
This patch makes the unwinder to use that offset when reading the RA
CFI register.
Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Some backends need to fine-tune the return address as fetched from the
corresponding CFI register. This patch adds a new backend attribute
ra_offset and the corresponding ebl_ra_offset getter function.
Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Mark Wielaard [Wed, 2 Dec 2015 16:27:18 +0000 (17:27 +0100)]
tests: Use valgrind --leak-check=full.
When --enable-valgrind is given run the testsuite with --leak-check=full
treating any memory leak as a failure. Also disable valgrind for those
tests that trigger a valgrind bug.
https://bugs.kde.org/show_bug.cgi?id=327427
Mark Wielaard [Wed, 2 Dec 2015 16:07:40 +0000 (17:07 +0100)]
libdw: Don't leak duplicate FDEs.
Although it isn't supposed to happen there could be FDEs that cover the
same address range. Don't leak such FDEs and use an existing FDE for
consistency.
Mark Wielaard [Wed, 2 Dec 2015 15:57:44 +0000 (16:57 +0100)]
nm: If the file is ET_REL and we need Dwarf use libdwfl to get it relocated.
If we need Dwarf and the file is ET_REL use the same trick as in readelf
to get a relocated Dwarf. Otherwise lots of references in the debug_info
will come out as zero.
This also explains the "bogus" Dwarf seen that caused the memory leak in
the local_root that was fixed previously.
Mark Wielaard [Tue, 1 Dec 2015 23:21:07 +0000 (00:21 +0100)]
libdw: Don't use a FDE if it doesn't actually cover a real code range.
If the FDE end <= start then it doesn't actually cover a valid code range.
Don't use and cache such FDEs (it will cause memory leaks if there is
another FDE that has the same start address and a valid code range).
Such FDEs have been seen in the backtrace.ppc.exec testfile.
Mark Wielaard [Tue, 1 Dec 2015 22:11:55 +0000 (23:11 +0100)]
libdwfl: Fix memory leak in link_map.c dwfl_link_map_report.
The phdrs buffer could come from the core file or through the executable.
dwfl_link_map_report would leak the buffer if it came from the executable.
Track where the buffer came from and free appropriately.
Mark Wielaard [Tue, 1 Dec 2015 21:16:00 +0000 (22:16 +0100)]
libdwfl: Don't leak core Elf and core file descriptor from argp-std.
Our argp helper would leak the core Elf and core file descriptor when
given by the user. Store both in the Dwfl as a new Dwfl_User_Core so
they get cleaned up by dwfl_end.
Mark Wielaard [Tue, 1 Dec 2015 14:21:55 +0000 (15:21 +0100)]
libdw: Don't leak fake_loc_cu.
The fake_loc_cu is used when synthesizing attributes for Dwarf_Ops that
came from a location list entry in dwarf_getlocation_attr. Make sure
we remove the loc cache stored in it when disposing of the fake_loc_cu.
Mark Wielaard [Thu, 19 Nov 2015 11:37:08 +0000 (12:37 +0100)]
libdw: Make sure Ebl is always freed from cfi frame cache.
libdwfl sets the Dwfl_Module Ebl for the eh_cfi and dwarf_cfi cache to
save a bit of memory. It also calls ebl_closebackend on the ebl to free
it. The Dwarf_CFI never frees the Ebl in the cache, even when it opened
one itself. This means that if only libdw calls are used to access the
Dwarf_CFI the Ebl might be leaked.
Always destroy the Dwarf_CFI cache Ebl in __libdw_destroy_frame_cache.
And in __libdwfl_module_free clear the Dwarf_CFI Ebl if it is the
Dwfl_Module Ebl before calling dwarf_cfi_end and dwarf_end.
Dmitry V. Levin [Mon, 16 Nov 2015 15:11:23 +0000 (18:11 +0300)]
libdw: initialize state early in read_srclines
Starting with commit f8443bd09f8a8d3d84a63e5ce206a218e57dff7a,
we might jump to "out" on error before initialization of "state".
Initialize "state" early to fix this issue.
Mark Wielaard [Fri, 16 Oct 2015 19:19:05 +0000 (21:19 +0200)]
elflint: Don't check shdr or TLS symbol offsets against debuginfo phdrs.
In debuginfo files the phdrs file offsets match those of the original ELF
file. So the section header file offsets and the TLS symbol value offset
in debuginfo files cannot be sanity checked against the phdrs file offset.
The issue can be triggered with run-strip-strmerge.sh test when configured
with --enable-gcov. Which will insert a .tbss section and TLS symbols that
trigger the above checks.
Mark Wielaard [Fri, 16 Oct 2015 11:15:01 +0000 (13:15 +0200)]
elflint: Reject mergable string sections as relocation target.
Mergable sections can be the target of a relocation, but only if they
contain items of the same size. So only reject mergable string sections
as target of a relocation section.
Mark Wielaard [Fri, 16 Oct 2015 10:26:27 +0000 (12:26 +0200)]
ppc: ppc_check_special_symbol): Also allow _SDA_BASE_ in .data section.
The Small Data Area Base normally points to .sdata, in which case we
check it is at an offset of 0x8000. It might however fall in the
.data section, in which case we cannot check the offset. The size always
should be zero.
Josh Stone [Sat, 10 Oct 2015 00:32:52 +0000 (17:32 -0700)]
libelf: Use int64_t for offsets in libelf.h
Some systems don't have loff_t, like FreeBSD where off_t always supports
large files. We need a standardized 64-bit signed type for the public
header, without depending on configuration... OK, just use int64_t.
Jose E. Marchesi [Tue, 13 Oct 2015 16:39:15 +0000 (18:39 +0200)]
Do not rely on ebl_check_special_section when checking debuginfo files.
The test run-strip-strmerge.sh is failing in sparc targets. This is
because it does an `elflint -d' in a debuginfo file, and this fails
with:
section [21] '.plt' is both executable and writable
elflint uses the ebl_check_special_section hook (implemented only by
the alpha and sparc backends) in order to determine whether an
executable+writable section must be flagged or not. In both cases the
hook will fail analyzing eu-strip debuginfo files (as they should,
because debuginfo files are broken ;).
This patch just modifies elflint to not use the hook when -d is
specified in the command-line. This fixes the test in sparc-* and
sparc64-* targets (and presumably in alpha* targets too).
Additionaly, the patch checks that the type of WE sections in
debuginfo files is NOBITS.
Signed-off-by: Jose E. Marchesi <jose.marchesi@oracle.com>
Mark Wielaard [Tue, 13 Oct 2015 14:02:10 +0000 (16:02 +0200)]
elflint: Check relro flags are a subset of the load segment.
If the RELRO segment doesn't fully overlap with the load segment then the
load segment might have more flags sets. This happens for example on sparc
when the .plt, which is executable, is also part of the load segment that
RELRO covers.
Mark Wielaard [Mon, 5 Oct 2015 15:32:29 +0000 (17:32 +0200)]
libelf: Only use posix_fallocate when using mmap. Ignore unsupported errors.
Don't use posix_fallocate when not using mmap. It is enough to ftruncate
the file to the right size. pwrite will report an error if there is no
disk space left. And on file systems that don't support fallocate it
might duplicate writes in that case. When using posix_fallocate do ignore
most errors. Other libc implementations don't guarantee the call actually
works always and even with glibc there might be an unexpected error from
the fallback code when the file system doesn't support fallocate. That is
pretty nasty since we might get a SIGBUS in that case when writing to the
mmapped memory. But the chance of that happening is very small. And will
normally never happen with glibc. So only report an error when
posix_fallocate reports ENOSPC.
Mark Wielaard [Wed, 7 Oct 2015 11:43:32 +0000 (13:43 +0200)]
config: Use ARFLAGS 'cr'.
By default automake uses ARFLAGS cru. 'u' is an optimization that
makes sure files are only added to the archive when they are newer
than the version already in the .a file. This optimization doesn't
work when ar is deterministic by default because then it doesn't
record timestamps in the archive. Deterministic ar is the default
now on various distributions causing multiple warnings like:
ar: `u' modifier ignored since `D' is the default (see `U')
Josh Stone [Fri, 9 Oct 2015 17:10:37 +0000 (10:10 -0700)]
Trust AC_SYS_LARGEFILE to provide large file support
AC_SYS_LARGEFILE defines _FILE_OFFSET_BITS in config.h if needed for
LFS, and this automatically maps things like open to open64. But quite
a few places used explicit 64-bit names, which won't work on platforms
like FreeBSD where off_t is always 64-bit and there are no foo64 names.
It's better to just trust that AC_SYS_LARGEFILE is doing it correctly.
But we can verify this too, as some file could easily forget to include
config.h. The new tests/run-lfs-symbols.sh checks all build targets
against lfs-symbols (taken from lintian) to make sure everything was
implicitly mapped to 64-bit variants when _FILE_OFFSET_BITS is set.
projects / thirdparty / elfutils.git / log
